At present, smart wristbands have been widely used in people's healthy lives, and are already in a trend to replace traditional wristwatches. Due to the small size of the smart wristband, the battery pack that can be placed is also small, and it is very urgent to minimize energy consumption during use. For a smart wristband with a larger display screen, when a user needs to check time, heart rate data or other functional data, the user needs to click on the screen by hand or press the button on the smart wristband by hand. When the user's other hand without wearing the wristband is in a state of being incapable of operating the smart wristband, the user obviously cannot simply light the screen to obtain the required information. Therefore, there is an urgent need for lighting a screen without the assistance of the other hand to meet the needs of the user. The conventional methods for the screen lighting of a wristband are generally implemented by detecting the flip angle of the wristband or using an altimeter to determine whether the user has a need to check time. However, this method is inaccurate. Sometimes the wristband is flipped several times and the screen is still not lighted, and sometimes a tiny motion may cause the screen to be always lighted. In addition, due to the habits of individual users, the smart wristband may be worn on either the left hand or the right hand. Every time a user changes the hand wearing the wristband, the user needs to set the hand wearing the wristband to be left or right, and then replace the algorithm for lighting the screen, depending on the left or right hand wearing the wristband.
The conventional methods for determining the screen lighting have the disadvantage of inaccurate determination and the disadvantage that it is necessary for the user to reset the state of the wristband worn on the left or right hand.